Threading-tool.



J.- J. FLYNN.

THREADING TOOL.

APPLICATION FILED JULY 30.1912.

1,%59,504. Patented Mar. 19, 1918 2 ISHEETSSHEETK 1.

1 72 3/ enivrx J. J; FLYNN.

THREADING TOOL,

APPLICATION FILED JULY 30.1917.

Patented Mar. 19, 1918.

2 s'HEETs-mmr 2.

X 2 $1602: 5 j [iii/ ora e JOHN J. FLYN'N, OF PROVIDENCE, RHODE ISLAND.

THBEADING-TOOL.

Specification of Letters Patent.

Patented Mar. 19, 1918.

Application filed July 30, 1917. Serial No. 183,411.

To all whom it may concern:

Be it known that 1, JOHN J. FLYNN, a citizen of the United States, residing at Providence, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Threading- Tools, of which the following is a specification.

My invention relates to threading tools and especially to die holders of the opening type adapted for use in turrets and other supports of screw machines.

The essential objects of my invention are to render the chasers and constituent parts of the device accessible; to insure the chasers against play whereby they would bell mouth; to securely hold the same under compression; to afford auxiliary adjustment for the chasers; to facilitate assemblage and disassemblage of the parts; to insure a maximum rigidity of all the parts during operation, as well as to maintain perfect alinement thereof; and to provide in a single structure means for finishing as well as for roughing the work.

To the above ends essentially my invention consists in such parts and combinations of parts as fall within the scope of the appended claims.

In the accompanying drawings which form a part of this specification,

Figures 1 and 2 are end and side elevations respectively of a threading tool embodying my invention.

Figs. 3 and 4, sections of the same on lines 33 and H of Fig. 1,

Figs. 5, 6 and 7, sections on lines 5-5, 6--6, and 77 respectively of Fig. 3,

Figs. 8, 9, and 10, details of one of the chasers,

Figs. 11, and 12, end and side elevations respectively of the casing or housing,

Figs. 13 and lt are end and plan elevation respectively of the cam actuating member,

Figs. 15 and 16, end and side elevations respectively of the chaser carrier; and

Figs. 17 and 18, similar elevations respectively of the spring retamer.

Like reference characters indicate like parts throughout the views.

The tool comprises a cylindrical housing or casing, comprising a body portion or shell 20, and a hollow stemv 22 intended for insertion into a turret, and constitute the supporting member for the parts. The shell'20 has an oblong slot 25 in its side provided with an inclined cam surface 26 at its end.

Slidable in the bore 27 of the stem is the hollow shank 28 of a hollow head 29 shown in detail in Figs. 15 and 16. The inner end portion 30 of the head is of less diameter than the intermediate portion 31, and the latter is of less diameter than the outer portion 32. The extreme outer end of the head is of maximum diameter forming a flange 33 adjacent which is a shoulder 34%. One or more diametrically disposed undercut or dovetailed guideways 35 are formed in the outer face of the head, and extend into the portion 32 of the latter. Cylindrical cavities 37 in alinement with each other in opposite sides of the portion 32 of the head open into the bottoms of the guideways and form longitudinal slots 38 therein.

Slidable in the guideway are the chasers 40 shown in detail in Figs. 8 to 10 inclusive. Each chaser comprises a body having flaring sides 42, and upon one end spaced fingers 43 carrying the cutter teeth 44. Upon its outer end each chaser has three curved shoulders. The upper shoulder or flange 46 extends beyond the intermediate shoulder or surface 47, while the lowest shoulder 48 is eccentric to the other shoulders and constitutes a cam surface. In the rear of each chaser near its outer end is fixed a pin 49. These pins extend downwardly into the cavities 37 through the slots 38 into the path of the caps 50, slidable in the cavities upon the outer ends of helical springs 51 seated in the cavities. The springs press outwardly and tend to distend the chasers.

A split ring 53 has a conical exterior slide face 54:, and its base abuts against the end face of the portion 23 of the casing. The space 55 between the ends of the split ring is ample to loosely receive a pin 56 in casing, and to allow a contraction of the ring.

This contraction is effected by a collar 58 provided with a conical opening 59 adapted to embrace the surface 5% of the split ring. In the rear end of the collar is an internal thread 60 engaging the thread 2A. A set screw 62 seated in a threaded opening 63 in the collar and adapted to engage the thread 24: serves to hold the collar in any axial position of adjustment.

Since the split ring embraces the flanges 1-6 of the chasers it is evident that as the collar in its rotation movesrearw ardly the ring 53 contracts and causes the cutting ends of the chasers' to' approach each other. The primary means for closing the chasers consists of a sleeve 65 r'otatably mounte dfu'p'on the portions 81 and 32 of the head 2-9 Within the casing'20, and shown in detail in Figs. 13'- and 14:. The end of this member abuts against the rear face of the step 34 of the head, and at diametrically opposite points the upper portion isfpro vided with marginal open slots 67, and centrally ofca'ch slot is a deeper slot 68. The resultant spaced shoulders 69 formed by the slots 67 have cam faces 7 0 and the portions of the sleeve adjacent the slots 68 are internally'cut away to form inclined surfaces 72. The described sleeve is manually turned a portion of a rotation by means of a handle 74' fast in'the'sleeve extending through the 7 slot 26. Since the cam faces48' on the chasers are in the path-of the shoulders 69 as the sleeveis turned, one of each pair of cam faces 7 0 moves over the faces 48 and conipresses the chassis so that the flanges 46 of the latter may enter the split ring 58.

Integral with or fixed to the head 29 by a screw 74 or otherwise is a collar 76 on which slides the rear face of the sleeve 65, and which is provided adjacent the latter with an annular channel 77. A pin 7 8 in dollar extends into this channel. A pin 7 9 on thesleeve65 also extends into this channel at a point opposite the first pin, A helical compression spring 80 is located in channel and bears against both pins at its ends.

In thisinstance bearing blocks 81 upon the ends of the spring contact with the pins.

This spring tends to rotate the sleeve 65 only, since the head 29, although longitudinally'slidable, is held against rotation by external lugs 83 on the collar 7 6 slidable in longitudinal grooves 84 in the casing 20'. The action of the spring is upon the1'n'emher in direction opposite to direction of manual movement of thehandle 74;.

For the purpose of moving the head 29 loi'igitudina'lly't'he stem 22 hasan enlarged bore 86 in its rear end in which is mounted acompression spring 87' engaging one'end 88 of the bore, and a collar or nut 89 slidable in the stem and having an internal thread 90 engaging an external thread 91 on the shank 28.

This collar is in the present instance threaded to make it possible, by screwing the same, to vary the tension on the spring 87. The latter acts to retract the head 29 rearwardly into the shell after the cam sleeve 65 has retracted the chaser's. holes 93 in the rear wall of the shell are convenient to prevent an air cushiOnwhen the headis retracted.

The operation of the parts thus far described is as follows: The stem being fast in the turret, the latter moves horizontally advancing the shell 22 together with the head 29' in the directioi'i of the arrow shown in Fig. 4, the desired distance of cutting. During this advance the work, while rectilineally stationary, is being rotated whereby the teeth of the chaser-s are enabled to cut the blank. At the moment the casing discontinues its advance the continued rota tion of the work cooperates with the teeth of the chasers to draw the head farther in the direction of the arrow against the tension of the spring 87 whereby the flanges 4630f the chasers advance beyond the split ring 53 and thereupon are expanded by the tension of springs 51, and the work is released.

The initial step in closing the chasers is effected as already described by partially r'otating the chaser closer or cam sleeve 65 by its handle until the flanges of the chasers are contracted sufiiciently to enter the bore of the split ring. The handle is then rearwardly induced by the cam 26 and the spring 87 whereby the head is pushed and drawn to bring the outer faces of the chas'-' er's back to original position. Micrometric adjustment of the chasers 18' next attained by turning the collar 58;

In the present instancea slight space 95' occurs between the end wall 96 of the shell 22 and the rear end of the head 29'to permit a rearward telescoping or yielding of the head. In this connection the latter hasicavi ties 97 in each ofwhich is a spring 98 pressing uponthe end of a slidable pin 99 which projects beyond the face of the head and contacts with the inner face of the casing wall 97. In the usual or roughing operation of the tlireading'tool the pins 99 may be removed as they are unnecessary. If, however, it is desired to finish a thread by recutting, the insertion of thev already threadediblank into the head so as to insure true registration of the old thread with 1, In a threading 110-01, the combination with the head and easing, of chasers yieldingly mounted in the head, a collar adjustably mounted on the casing and provided with a cam opening, and a split ring registering in said opening and embracing the head and chasers.

2. In a threading tool, the combination with the head, of chasers yieldingly mounted in the head, a casing exterior of the head provided with a thread, a yielding ring abutting against the "casing and embracing the chasers, and a collar slidably embracing the ring and provided With a thread loosely engaging the first thread.

3. In a threading tool, the combination with the head provided with radial cavities, chasers slidably mounted in the head in alinement with the cavities, pins on the chasers extending into the cavities, springs in the cavities engaging the pins, a casing surrounding the heads, a yielding member embracing the chasers, and a cam collar embracing the yielding member adjustably mounted on the asing.

i. In a threading tool, the combination with the casing provided with an oblong opening, of a head mounted in the casing, a rotary sleeve upon the head provided with open marginal slots, cam shoulders on the sleeve at the sides of the slots, a handle in the sleeve extending through the opening, chasers yieldingly mounted in the head in alinement with the slots, cam faces on outer ends of the chasers adapted to engage the cam shoulders, a split ring embracing the chasers and provided with an inclined outer face, and a collar embracing the ring and adjustably mounted on the casing.

In a threading tool, the combination with the casing provided with an oblong opening, of head mounted in the casing, a rotary sleeve upon the head, cam shoulders on the sleeve, a handle in the sleeve extending through the opening, a spring in the head impelling the sleeve and head in opposite directions, chasers yieldingly mounted in the head, cam faces on the chasers in the path of the cam shoulders, and a collar on the casing surrounding the head. v

6. In a threading tool, the combination of a casing provided with an opening and with longitudinal grooves, a longitudinally slidable head mounted in the casing, lugs upon the head registering in the grooves,'a rotary cam sleeve upon the head, resilient means for actuating the sleeve, a handle on "he sleeve extending through the opening, a collar on the sleeve surrounding the head, chasers yieldingly mounted on the head, and springs in the head engaging the chasers.

7. In a threading tool, the combination of a casing provided With an opening, a longitudinally slidable head mounted in the casing, chasers yieldingly mounted in the head, a. resilient member embracing the chasers, springs in the head pressing the chasers against said member, a collar adjustably mounted on the casing embracing said member, a rotary cam sleeve upon the head adapted to engage the cams in its rotation, an arcuate spring engaging the cam sleeve and head, and a handle on the sleeve extending through the opening.

8. In a threading tool, the combination of a casing provided with an opening, a stem upon the casing, a longitudinally slidable head mounted in the casing, a shank upon the head slidable in the stem, a spring upon the shank engaging the stem, chasers yieldingly mounted in the head, means upon the casing for retaining the chasers, an oscillatory cam sleeve upon the head movable into the paths of the chasers, and a handle on the sleeve extending through the opening.

9. In a threading tool, the combination of a casin provided with an opening, a stem upon the casing, a longitudinally slidable head mounted in the casing, a shank upon the head slidable in the stem, an adjusting nut on the end of the shank Within the stem, a spring upon the shank having one end abutting against the nut and the other end engaging the stem, chasers yieldingly mounted on the head, means upon the casing for retaining the chasers, a reciprocating cam sleeve upon the head adapted to engage the chasers, and a handle on the sleeve extending through the opening.

10. In a threading tool, the combination of a casing providedv with an opening, a stem on the casing, a longitudinally slidable head mounted in the casing, a shank upon the head slidable in the stem, a spring upon the shank engaging the stem, chasers yieldingly mounted in the front end of the head, means upon the casing for retaining the chasers, an oscillatory cam sleeve upon the head movable into engagement with the chasers, a handle on the sleeve extending through the opening, and yielding members engaging the rear end of the head and the casing.

11. In a threading tool, the combination of a casing provided with an oblong opening, and with a cam face at one end of the open'in a longitudinally slidable head mounted in the casing, chasers yieldingly mounted in the head, a cam sleeve loose on the head adapted to engage the chaser, and a handle fast to the sleeve extending through the opening adapted to engage the cam face.

12. In a threading tool, the combination of a casing provided with an oblong opening, and with a cam face at one end of the opening, a longitudinally slidable head mounted in the casing, chasers yieldingly mountedin the head, an oscillatory caniv a shank on. the headslida'ble in the stem, a sleeve loose on the'head adapted to engage spring upon the shank engaging the stem, the chasers, a handle, fast to the sleeve exchasers yieldingly mounted in'the head, an tending through the opening, and spring oscillatory cain sleeve upon the head mov- 15 means within the casing for oscillating the able into engagement with the chasers, and

iandle in one direction. a handle on the sleeve extending through the 13'. In a threadlng tool, the conibinatlon opening. I of a caslng provided with an oblong open- In testnnony whereofI have aflixed my ing, and with an inclined cam face at one signature. end of the openlng, a stem on the caslng, a longlti'lchnally shdable head in the casing, JOHN J. FLYNN.

Gopie'of this patent'may be obtained for five cents each, by addressing the "Commissioner ofiPatents;

Washington, D, G. 

